Trailer lights that always work

Photo 1: Assemble the new harness

Run the new harness and the
extra ground wire through the
split loom tubing. The loom
protects the harness from
rub-through and shorting
inside the trailer frame.

Photo 2: Tape and pull

Strip the ends of the new
harness wires and secure
them to the mason's line.
Then wrap the entire connection
with electrical tape
to make sure it doesn't come
apart during the pull.

Photo 3: Crimp and shrink

Connect the lighting
and ground
wires to each light
with a crimp connector
and heat-shrinkable
tubing.
Then splice all the
individual ground
wires to the harness
connector
ground wire.

When it comes to trailer lighting, nothing causes
more trouble than burned-out bulbs and corroded
ground connections at the frame. Rubbing (and
shorting) connections come in a close second.
If you want to get rid of those problems forever,
switch over to LED lights and add an individual
ground wire to each light. The entire project takes
just a few hours.

The trailer light kit we used (Blazer International
No. 127680; about $54 from amazon.com)
comes with a new harness. At an auto parts
store, buy a spool of 16-gauge wire for the individual
ground wires. Then buy crimp connectors
and a few packages of split loom wiring harness
protectors (Curt Manufacturing No. I-1824-25;
25-in. length; from amazon.com).

Disconnect the old trailer harness wires at each
light and attach mason’s line. Then pull each
line back toward the trailer tongue. Connect this
“fishing line” to the new harness and loom (Photo
1). Next, pull the new harness through the frame
(Photo 2). Finish off the installation with crimp
connectors and heat-shrinkable tubing (Photo 3).